1. Field of the Invention
The present invention generally appertains to new and novel improvements in cutting blades and is particularly directed to a new and novel razor blade for use in surgical shaving.
2. State of the Art
The provision of razor blades with an integral or self-contained guard in the form of spiral windings of a flexible wire is well-known in the art. One of the earliest prior art proposals can be found in U.S. Pat. No. 1,035,548 issued on Aug. 13, 1912 to Dickenson. In such patent, a straight razor is disclosed with the blade thereof having a wire spirally wound therearound so as to form some type of guard. As is clear from FIG. 1 of such patent, the windings are widely spaced along the cutting edge of the blade on an unspecified arrangement.
There is no suggestion in such patent of any criticality in such spacing of the windings of the wire nor of the diameter of the wire.
More recently, U.S. Pat. No. 3,505,734 was issued to Iten on Apr. 14, 1970. The razor blade of Iten follows the general teachings of Dickenson but complements the same in establishing a criticality between the spacing of the windings of the wire and the wire diameter dimensions. Iten recognizes the importance and criticality of the diameter of the wire or thread and the spacing between adjacent turns or windings of the wire or thread.
The razor blade of the Iten patent is primarily intended for shaving terminal hairs on the facial areas of the body and the specified critical values of the spacing of the windings of the thread are based on the normal facial hair sizes.
In this regard, it must be recognized that the epidermis of the face is dissimilar from the epidermis of the other portions of the body, such as the abdomen or pubic areas. The epidermis of the face can withstand greater irritation than the epidermis of the abdomen or other areas of the body, having regard to shaving of the hairs. The facial areas are shaven on a daily or regular schedule, whereas other areas of the body, being prepared for operations, are shaven generally on a one time only basis. Also, the cross-sectional shape and size of the hairs on the facial areas are very different from the cross-sectional shape and size of the hairs found on the body.
Because of such differences, the razor blade of the Iten patent would not be particularly usable for preparation of an operative site or preparation of a body area at a proposed intraveneous or intraarterial catheter or injection location even though Iten has suggested such use.